diff --git a/README.md b/README.md
index 83df6e5..0f19ef3 100644
--- a/README.md
+++ b/README.md
@@ -70,11 +70,33 @@ Input course number(m<=%d):
 Management for Students' scores
 1.Input record
 2.Calculate total and average score of every course
+3.Calculate total and average score of every student
+4.Sort in descending order by score
+5.Sort in ascending order by score
+6.Sort in ascending order by number
+7.Sort in dictionary order by name
+8.Search by number
+9.Search by name
+10.Statistic analysis
+11.List record
+12.Write to a file
+13.Read from a file
+0.Exit
+Please Input your choice:   //用户输入选项后将结果返回到主函数
+
 ```
-### C3:计算每个学生各门课程的总分和平均分
+### C3: 计算每个学生各门课程的总分和平均分
+
+选择菜单命令2，通过学号查找到该学生的结构体，通过结构体找到各科的成绩，然后进行求和和平均
 
+```
+stu[i].sum+=stu[i].score[j];//求和
+stu[i].aver=stu[i].sum/m;//求平均
+```
 ### C4:计算每门课程的总分和平均分
 
+选择菜单命令3
+
 ### C5:按每个学生的总分由高到低排出名次表
 
 ### C6:按每个学生的总分由低到高排出名次表